Baptisia arachnifera, commonly known as hairy rattleweed, cobwebby wild indigo, hairy wild indigo, and hairy false indigo, is an endangered species of flowering plant in the legume family. Its native habitat is limited to sandy soils in pinewoods along the coastal plain of the U.S. state of Georgia.
Wilbur H. Duncan first described this species in 1944 after collecting a specimen in 1942 from a site in Wayne County, Georgia.
Baptisia arachnifera is a perennial that grows to a height of forty to eighty centimeters and is "covered with grayish-white, cobwebby hairs". Blue-green, simple leaves are alternate and heart-shaped. They range in size from 2–6 cm long by 1.5–5 cm wide.
Flowers form in terminal racemes with five bright yellow petals and bloom in late June through early August.
Fruits are woody pods 8–15 mm long and 6–9 mm wide with stalks and beaks,